Recently there has been a catalog of British Malaya (incl. Straits Settlements) available in the PCN library. This catalog was offered by PCN member William Baekers.
The booklet was published by P. Giffen from New Zealand, measures 12.5 by 15 cm and consists of 32
black and white pages. Furthermore, the booklet has an index regarding the difficulty of the perfins.

The catalog can be borrowed from librarian Pieter Gommans. Send him an email if you are interested and he will bring the catalog at the next PCN meeting for you.